This game has unused areas. This game has unused code. This game has hidden development-related text. This game has unused modes / minigames. This game has unused graphics. This game has unused items. This game has unused text. This game has debugging material. This game has regional differences.

Pokémon Gold and Silver is one of the most extensive Pokémon games, featuring 100 new Pokémon (a 66% increase!), new game mechanics like hold items and two new types, and allowing the player to return to Kanto, featured in Red and Blue, as part of the storyline to work his way up to beat the ultimate trainer, Red.

Sub-Pages

Debug Menus

Pokémon & Trainer Color Test Menu

This color test menu is basically a menu to easily change the color palettes of Pokémon, both normal and shiny palettes, and trainers as well as to conveniently list if a Pokémon is capable of learning a Technical Machine (TM) or Hidden Machine (HM). The menu code is located at 3F:54F1 in the Japanese ROM (v1.0 and v1.1) and the screen update service has to be enabled (register FFD6 must be checked). Other language version ROMs have the code as well, but due to the screen not being localized, graphic bugs ensue.

You have to select either Pokémon or trainer mode before loading the menu by setting CF21 to 0x00 for Pokémon mode and any other value for trainer mode.

First Page

The first page is for color adjustment and sprite viewing. Beware: altered colors will not be retained when switching between normal and shiny colors! They will be retained when changing between Pokémon/trainers though!

Navigation: The D-Pad selects either the color to manipulate, or the color's red, green, or blue channel. Press A to switch between normal and shiny colors for Pokémon, while pressing B will switch to the second page. Select and Start change sprites going forwards resp. backwards through the sprites in PokéDex order resp. internal order for trainers.

Colors: The Pokémon's/trainer's two colors are represented by their color and their hexadecimal values below each color panel in the top-right of the menu. You can change the colors freely for each color channel separately.

Strings: The Pokémon's/trainer's number along with the associated name will be printed in the top-left. On the bottom appears the palette name that the Pokémon is currently being displayed in. 「Ａきりかえ▶」 means "A switches", 「ノーマル」 means "normal [palette]", 「レア」 means "rare [shiny palette]".

The first page upon starting the menu.

The first page with shiny color selected.

The first page with altered shiny color.

The first page with Trainer Beauty selected. Notice the text running into the color panel.

The first page with altered regular colors.

Second Page

The second page is for exiting the menu and viewing the TMs and HMs the Pokémon can be taught. Things from the first page, such as the Pokémon's name, images, and colors will be shown on this screen, too. In trainer mode, this menu will still act as if a Pokémon was selected and show the respective Pokémon's data.

Navigation: The D-Pad selects the TM/HM. B switches to the first page. Although the screen says that the user can exit the menu by pressing A, the actual code (while still in the ROM) is never executed, probably due to the actual check for the A button having been commented out.

TMs/HMs: Machines have their name stated on the right-hand side. Right below the name is an indicator whether the Pokémon can be taught the selected machine or not.

Strings: 「おわりますか？」 means "Are you finished?", 「はい」 being "yes" and 「いいえ」 being "no". 「おぼえられる」 and 「おぼえられない」 mean "can be taught" and "cannot be taught" respectively.

The second page showing that Pupitar cannot be taught Mega Punch.

The second page showing that Pupitar can be taught Headbutt.

The second page showing that Beauty can supposedly be taught Headbutt.

Tileset Color Menu

While the actual routine that procures this menu has been commented out, as evident by a single ret before all subroutines of the menu, with the right code it can still be used. This menu's main task was to grant the user the ability to edit the current palettes used for the current background tileset.

To get the menu in-game, one needs to write custom code that loads the menu. For the Japanese version, the following code can be placed anywhere in ROM bank 0x3F. It can then be called from an in-game event, such as a signpost, via the 3byte pointer ASM command (see Gold & Silver Scripting Compendium for further info).

Navigation: The D-Pad selects the current palette's color to manipulate on the top row, or the selected color's red, blue, or green channel (from top to bottom respectively). Press Select to rotate through the palettes in order in which they are loaded in RAM, although it is not possible to edit palette 0x07, the menu palette, or any foreground palettes. B hides resp. shows the menu, probably so the user can inspect the whole map screen rather than only the top portion. While the menu is hidden, it still functions the same as if it was shown, meaning colors can be selected and edited as usual.

Colors: The current palette's four colors are represented by their color and their hexadecimal values above each color field in the top row of the menu. One can change the colors freely for each color channel separately.

There is no means to exit the menu, as the respective code was probably commented out as well.

The screen upon starting the menu.

The screen after editing the first palette's first and last colors, which are used on the signpost to the right and on the ground, obviously.

The hidden menu. The color channel arrows are still shown.

The menu with palette 0x01, the house and flower palette, selected.

Unused Text

To do:Japanese text

All text offsets are for the American version of Gold and Silver.

Location Names

The following location names are in the location name table alongside other location names, but are unused.

0x092641: N/A

0x0926FD: LAV RADIO TOWER

0x09270D: SILPH CO.

0x092717: SAFARI ZONE

0x092733: POKéMON MANSION

0x092740: CERULEAN CAVE

0x092910: VIRIDIAN FOREST

Others

Placeholder for objects with no script.

0x190262: "That can't be used right now."

0x190280: "That item can't be put in the PACK."

0x1902A4: "The " (string from 0xCF6B) " was put in the PACK."

0x1902C4: "Remaining Time"

0x1902D4: "Your POKéMON's HP was healed."

0x1902EF: "Warping..."

0x1902F9: "Which number should be changed?"

0x19031A: "Will you play with " (string from 0xCF7E) "?"

0x190335: "You need two POKé- MON for breeding."

0x190358: "Breeding is not possible."

0x190373: "The compatibility is " (number from 0xD151) ". Should they breed?"

0x1903A4: "There is no EGG. "

0x1903B7: "It's going to hatch!"

0x1903CC: "Test event " (number from 0xCF7E) "?"

0x1903E0: "What do you want to play with?"

0x190400: "You can have this."

0x190414: "The BOX is full!"

0x190426: "Obtained the VOLTORBBADGE!"

0x190442: "The password is:"

0x190455: "Is this OK?"

0x190462: "Enter the ID no."

0x190474: "Enter the amount."

0x195B29: "The window save area was exceeded."

0x195B72: "Corrupted event!"

0x124558: "Oh, no. Oh, no… My daughter is missing. No… She couldn’t have gone to the BURNED TOWER. I told her not to go near it… People seem to disappear there… Oh, what should I do…?" (This may indicate a subquest for the Burned Tower was scrapped, or moved to the SS Aqua.)

0x195B93: "BG event" (likely a placeholder for "invisible" events such as signs)

(Unknown offset:) "?" (item identifier 00 or rival's default name before getting named automatically as "???")

0x195B84: "Object event." (placeholder for events connected to NPCs)

Leftovers from Red, Blue, and Yellow

The following strings of dialogue (from the US ROM image) are not used within the final version of the Gold and Silver but are leftovers from the Red and Blue engine. The unused BIRD type is also still in the engine.

0x050A3A: BIRD

"It dodged the thrown BALL! This POKéMON can't be caught!"

"You missed the POKéMON!"

"Played the POKé FLUTE."

"Now, that's a catchy tune!"

"All sleeping POKéMON woke up."

"[PLAYER] played the POKé FLUTE."

Invisible Game Mechanics

The following game mechanics, if forced to be referenced via a dialogue string (though they never are in normal gameplay) will display:

Professor Oak's picture: "POKéMON PROF." (stored with trainer class data, though it is only referenced on the introductory screen to point to Professor Oak's picture; not in a trainer battle, so "POKéMON PROF." is not displayed.)

Last location placeholder: "SPECIAL" (A town map name, though the name "SPECIAL" can't be seen in normal gameplay; its identifier is 00 to reference the last town map name loaded into the game's memory instead:- useful for Pokémon Centers)

Player's back-sprite in battle: "?????" (The game references the backsprite of undefined Pokémon #252 "?????")

Voltorbbadge

The Voltorbbadge is probably an in-joke, because other badges have receive text in the format Player received NAMEBADGE.

SILPHSCOPE2

Arguably was supposed to be used instead of the SquirtBottle, as suggested by an unused dialogue string:

"I hear there's a POKéMON that looks just like a tree.
You can reveal its identity using a SILPHSCOPE2."

Test Event

Non-functional text.

This is one of the fragments of debug text left in the game. There does not appear to be any of its code left. The RAM address it displays is actually data from the real-time clock, which makes little sense here, suggesting the code was removed before the clock was added.

Mr. Chrono

To do:Is he in Crystal as well?

A leftover script in New Bark Town. While it claims to be activating a debug mode, unfortunately all that seems to be left is the text, which displays the real-time (RT) read from the clock and the time difference (DF) set by the player as well as whether daylight saving time is on or off. There is also text nearby from a function that would calculate the clock reset password for you.

This feature was added for the localizations of Gold and Silver, probably to check whether daylight saving time was working correctly. The Japanese and Korean versions do not have this leftover, as daylight saving time is not used in Japan and South Korea.

Sweet Honey

Text about "sweet honey" appears in the ROM. It's possible that Sweet Honey was a concept that was canned (or reworked into Headbutt or Sweet Scent) and reimplemented several years later, in the form of Honey in Diamond and Pearl.

My POKéMON is an
expert at collect
-ing SWEET HONEY.
I’ll share some
with you.
I want to give you
some SWEET HONEY,
but you have no
room for it.
Here you go! Have
some SWEET HONEY!
{A1} received
SWEET HONEY.
My little brother
takes SWEET HONEY
and goes somewhere
with it.
I wonder what he’s
up to?
Did you put SWEET
HONEY on a tree?
What happened to
it?
Did you put SWEET
HONEY on a tree?
It takes about a
day for POKéMON to
be drawn to it.
BUTTERFREE: Freeh!

Unused Functions

Naming Your Mother

To do:What about Crystal?

Animation of the naming screen for the player's mother.

Naming the player's mother is fully functional in Gold and Silver. However, during the DUDE's Pokémon-catching tutorial, the player's name is copied to the RAM location of the mother's name, hence implying that the player names his mother at a stage where the tutorial cannot be accessed anymore. The name itself can be displayed in text via byte 49 and should have 11 tiles reserved in the text box to safeguard against overflowing text.

When RAM is initialized at boot, the player's mother's name is initialized to MOM.

Extra Field Move Entries

PAY DAY (ID 00) - apparently this would have been usable outside of battle at one point. Attempting to use it now only crashes the game, as it's been deleted from the pointer table.

ERROR! (ID 15) - the last entry. No other menus have such entries, so this may be a deleted move. Like PAY DAY, this item has no entry in the pointer table, but by chance the game manages to not crash and simply does nothing when this is used.

The pointer table for the abilities also shows some interesting facts:

The table is in fact a map (unordered ID->pointer pairs), rather than an array. The reason for this is not clear.

The game checks for a terminating entry in this list (pointer 0000); if it finds this entry before the ID it's looking for, it will just return without doing anything. However, the list doesn't actually have a terminating entry, so Pay Day and Error will cause it to read past the end of the list looking for them, eventually finding an invalid pointer for Pay Day and a terminating entry in the following data (thus why Error does nothing).

The out-of-order keys suggest that Waterfall was added later in development; it appears near the end rather than being grouped with the other HM moves.

To see the unused menu options, enter one or both of the following GameShark codes and select a Pokémon with one HM ability: 0100D5D0 for Pay Day, 0115D6D0 for "Error!".

Unused Battle Types

The RAM address D119 determines the "type" of battle which is taking place. There are a few entries which are never normally used in normal gameplay.

Battling with no Pokémon

This battle type is identifier 0x02. The player enters battle without sending out any Pokémon, however none of the functions appear to have been defined. All functions other than PACK and RUN instantly end the battle, whereas PACK and RUN function as they would in a typical battle.

Unlike the DUDE's demonstration, this battle does not change the player's sprite, automatically throw a POKé BALL once the item pack is closed, or copy the player's name to the RAM location of the mother's name.

Always battle female Pokémon

To do:Specific DVs

This battle type is identifier 0x05. It causes the player to always battle a Pokémon with DVs matching a female Pokémon (if possible). For unknown reasons, there does not seem to be a matching battle type for encountering male Pokémon.

Automatic Battle End

This battle type is identifier 0x06. It causes the battle to end as soon as the player sends out their first Pokémon. Although it is ultimately unused, it is called automatically when the player attempts to enter a Trainer battle without any Pokémon. There is another function, though unrelated to this byte which causes wild Pokémon battles to end before they start.

It can also be triggered by a glitch, which lets the player walk around with no usable Pokémon, if the player obtains a ????? (FF) first using the Bad Clone glitch, faints all of their other Pokémon beneath it, and then gets whited out.

Extra Experience Groups

To do:The level 100 experiences don't follow those formulas. Check whether +30 and +70 is supposed to be -30/-70.

In addition to "Fast", "Medium-Fast", "Medium-Slow", and "Slow", two other groups closely related to "Medium-Slow" are programmed into the game but never used:

Maximum EXP: 849,970

Maximum EXP: 949,930

They rise pretty much as slow as "Medium-Slow" but offer less maximum EXP. The maximum EXP of "Medium-Slow" is 1,059,860.

(Source: DevZ)

Clock Reset

By pressing ↓ + SELECT + B at the title screen or using GameShark code 010464CE and pressing START or A, the player can access a clock reset screen. The function requires a password which is calculated from various game state information. The Japanese versions do not contain this clock reset function.

When doing this on an empty battery, where it is impossible to type the correct password, the game resets and runs with a strange graphics bug.

Passwords can be calculated online at Filb. Changing address 23:4225 (or offset $8C225) from 37 to C9 will make incorrect clock reset passwords work. This equates to the Game Genie code C92-25B-3B6.

To use any password, either modify the byte of address 0x4226 to 0xC9 from 0x37 or use Game Genie code C92-26B-3B6.

To do:Is it really absent from the Japanese games or is it just completely unused?

Movement Type 02

In Gold and Silver, there is a byte that manages different movement types. In the English Gold and Silver, this byte has the address D682. Four of the movement types are used: 00 for walking, 01 for cycling, 04 for surfing, and 08 for surfing Pikachu. 02 functions like sliding on ice, however it is actually unused – D682 doesn't change to 02 when sliding on ice in the Ice Path.

Movement type 02 may have been an early implementation of sliding on ice before the final mechanics of sliding were programmed into the game.

Generation I Mimic Menu

In Japanese Gold, Silver and Crystal, the old menu for using Mimic from Generation I exists in the code unused, complete with the message "どのわざを ものまねする?" ("Mimic which move?"). It can be accessed by opening the fight menu with the code 010111D1 (Japanese Gold/Silver) or 010166D2 (Japanese Crystal) on. It is not possible to back out from the menu.

In normal gameplay of Gold, Silver and Crystal there is no Mimic menu. Instead, Mimic copies the last move that the opponent used, unless it is a move the user already knows, Sketch, Struggle, Metronome, or if no move was used.

Accessing it with these codes may bring up the user's moves instead of the opponent, and using a move may force the user to use Struggle. It is unknown if this is a limitation of opening the menu this way or if the menu is buggy.

The equivalent code for bringing up this menu in the English versions seems to be 01011FD1 (English Gold/Silver) or 010135D2 (English Crystal), and these codes will disable backing out from the menu, but this code does not change how the fight menu looks other than disabling the type/PP box. In at least English Crystal, when the menu is opened the game tries to print text from offset 0x3e61c, but the only thing there is a 50h control character, meaning no text is displayed. The coordinates on the screen of the beginning of the text in English Crystal are at x=0B, y=0E (BGB coordinates); the same as the beginning of the Japanese message, suggesting that the text was 'dummied out'.

Unused Memory Game

The Game Corner in Gold, Silver, and Crystal has two kinds of machines: a slot machine and a card flip table. However, there is an unused third game which is mostly working – namely, a memory game, which can only be activated with a Coin Case as well as some coins.

Use the D-Pad to move the cursor, and press A to flip the selected card to see what kind it is. There are three different difficulty levels that affect the random placement of the individual card faces, probably one for each coin selection – one coin, two coins, or three coins. CF14 is the difficulty option, from 01-03.

As this is a memory game, you have to find matching pairs of cards. If the flipped cards match, they are removed and the card will be displayed at the top of the screen. If they don't match, both will be flipped back. You have five tries to find matching pairs, after which the game just deals another set of cards.

とったもの ("[Cards] taken") in the upper-left corner shows the cards you have matched, and あと#かい ("# more turns") is how many tries you have left. Getting a match shows ＣＡＲＤ いただき！ ("CARD, yeah!") and picking the wrong cards shows ざんねん... ("Darn...").

Note that the cursor is usually garbage, as the graphics data was commented out as well. Therefore, the PokéGear indicator is used in the video.

The actual routine that would let you choose the difficulty level, award prizes, and even exit the game doesn't exist, so there is no way to win or exit outside of resetting the game.

See the Notes page for a fully commented disassembly of the Memory game.

Tilesets

Early Tileset

The mock-ups were modeled after this magazine scan.

The Japanese v1.0 ROM's offset for the early block data is 06:6BA0 and the offset for early collision data is 06:73A0. These follow right after the block data of regular tileset 0x02, the Goldenrod City tileset. These were used to dump the early city maps above.

The tileset used is a mockup based on earlier leftovers in tileset 01, the regular city tileset which still contains parts of the pagodas at the exact location the early blockdata uses. Only a total of six tiles have been added to produce the early version mockup tileset.

As can be seen, the block data was changed after the early city maps were created and then presumably copied over to a then-new tileset 0x02 and split to tileset 0x01 thereafter and then forgotten about. This is especially visible in Olivine City's map, where the light house now has parts of mountains instead of the proper tower parts. Also, block 0x0D was deleted for whatever reason, hence it was rendered as a black block on both Goldenrod City's and Olivine City's map. The evolution goes from Tileset 0x1F to tileset 0x20 that resembles an intermediate to tileset 0x01's final layout.

Early Collision Data

There is an extra 0x60 bytes after the collision data at 37:7E33 in the Japanese v1.0 ROM just after the Ilex forest (tileset 0x1C) collision data that allow for 0x18 more blocks than the current tileset features. Curiously, the block data does not have room for 0x18 more blocks, meaning that this may or may not have been part of the Ilex forest tileset collision data.

However, since their contents are static, it suggests the former. The blocks would have had the following layout. Each cell corresponds to one fourth of a block, the size of an in-game person:

Solid

Walkable

Solid

Walkable

Unused Tile Palette Assignment Data

At 02:4547 in the Japanese v1.0 ROM there are 0x30 bytes of tile palette assignment, which assigns a palette for each tile of a tileset, that go unused. The layout is as follows, where the second color of each palette represents the palette overall pretty well:

Seems to be a nice fit.

This seems to fit tileset 0x09 from Red/Green/Blue/Yellow. Notice how the carpet at tiles 0x37 and 0x38 is blue instead of the usual red, which the dark shades of the Game Boy would have suggested.

Tileset 0x06 (Pokémon Center)

The tileset in the production ROM contains blocks for a Red/Green/Blue/Yellow-style Pokémon Center that are never actually used.

RGBY

GSC

Also, this tileset contains a block that is never actually used whose tile has the wrong palette associated with it (red instead of blue). It may have gone unused because of this error.

Tileset 0x15 (Caves)

Minecart and some tracks.

The cave tileset features some infamous tiles for a mine cart and some tracks. However, no blocks ever use these tiles at all.

Tileset 0x17 and 0x1A (Ruins of Alph and Hall of Fame)

These two tilesets share a 2×2 ground tile, indicating that tiles might have been shifted from one tileset to the other somewhat late in the production cycle. Also notice how the color assignments of the Hall of Fame tileset hint at deleted tiles.

Ruins of Alph

Hall of Fame

Tileset 0x1C (Ilex Forest)

Unused signs and sand tile.

Ilex Forest contains two sets of tiles for the signpost, one duplicate and one unused. This was probably a last-minute change and included to be able to reverse back at any moment. Also, Ilex forest does not feature any blocks with sand on them, making this standard tile go unused within the forest.

Unused Trainer Rosters

Pokémon Trainer Cal from Viridian City's Trainer House is normally only accessible late in the game, where he faces the player with the Johto starters in their final evolutionary forms at Level 50, provided that Mystery Gift was not used. Despite this, other rosters associated with Cal still exist within Gold/Silver/Crystal:

Unused Move Effects

To do:Further research is needed, as this list likely isn't exhaustive. Find out whether items like the Poké Doll get their effects from normally unused move effects. (there are effects to raise accuracy and escape)

Like Red and Blue, Gold and Silver (as well as Crystal) have some move effects for raising and lowering all stats, meaning some of the move effects like 'raise evasion two stages' are unused. Additionally, there is a move effect to cause the opponent to always flinch, unless the user is slower than the opponent (in this case the move will always miss) but this effect deals no damage.

Changing offset at 0x41AFF in Gold or at 0x41AFC in Crystal will modify the move effect of Pound.

All of the below effects deal no damage.

Identifier

Effect

0C

Raises user's Speed by 1 stage.

0E

Raises user's Special Defense by 1 stage.

15

Lowers enemy's Special Attack by 1 stage.

16

Lowers enemy's Special Defense by 1 stage.

35

Raises user's Special Attack by 2 stages.

37

Raises user's Accuracy by 2 stages.

38

Raises user's evasion by 2 stages.

3D

Lower's opponent's Special Attack by 2 stages.

3E

Lowers opponent's Special Defense by 2 stages.

3F

Lowers opponent's Accuracy by 2 stages.

40

Lowers opponent's evasion by 2 stages.

8D

If user is faster, cause the opponent to flinch but deal no damage. If user is slower, always miss, even when Mind Reader was used the previous turn. (video)

Other Unused Content

Teru-sama

To do:Are there usable Teru-sama different in other versions, such as the Japanese ones?

Teru-sama is simply a set of placeholder items used by the game to fill up empty item slots and prevent crashing when the data is loaded. Most Teru-sama are useless and only give the "GIVE/TOSS/QUIT" options but there are two Teru-sama that function as items, though: the Town Map and Poké Flute from Red, Green, Blue, and Yellow are still present in the internal data. Most of the other Teru-sama if forced to have a "USE" option will display Professor Oak's "This isn't the time to use that!" message. Teru-sama with unique effects include identifiers 06h, 38h and BE, however BE has an invalid pointer and was likely never intended to have a "USE" option.

The 06h Teru-sama works as a faulty version of the Town Map from Red, Green, Blue, and Yellow.

The 38h Teru-sama works as the Poké Flute if a "USE" option is forced (video). Like in Red, Green, Blue, and Yellow, it can be used to wake up sleeping Pokémon in the player's party in and outside of battle. The Poké Flute sound plays if the player uses the item outside of battle with a sleeping Pokémon but not if the player doesn't have a sleeping Pokémon in the party or uses the item with a sleeping Pokémon in the party within a battle.

Teru-sama can be sold for 19,660 Pokémon Dollars (yen in Japanese versions and won in Korean versions) at Poké Marts. Its buy price of 39,321 Pokémon Dollars equals 0x9999, or 9999 in binary-coded decimal, the format Red, Green, Blue, and Yellow use for monetary values. Gold, Silver, and Crystal use plain binary integers for money instead of BCD; however, the buy Teru-sama price indicates that Gold and Silver did use BCD earlier in development.

The name Teru-sama used in the Western versions may be a reference to Teruki Murakawa, a programmer that appears listed in the credits of the English and European versions of Gold, Silver, and Crystal and as a coordinator in the Korean versions of Gold and Silver. In the Japanese versions, these items are called Kabichuu (カビチュウ), which may be formed from the combination of "kabi" in Kabigon (Snorlax) and the "-chuu" of Pichu, Pikachu, and/or Raichu. In Korean Gold and Silver, Teru-sama have a fullwidth question mark "？" as their name.

The Crystal-exclusive items Clear Bell, GS Ball, Egg Ticket, and Blue Card correspond to Teru-sama in Gold and Silver. In Korean Gold and Silver, the equivalent Teru-sama (except for the Egg Ticket) were renamed to match their Crystal names but their functionality remains unaltered.

Shiny Mew

For the sake of consistency, every Pokémon in every Pokémon game is given a Shiny variant, including Mew. However, all Mew distributed to Generation I games have a fixed set of DVs that prevents them from becoming Shiny when traded to Generation II games, leaving its Shiny form unobtainable without cheating or glitches (the Trainer-Fly glitch, for example, would produce a Mew with random DVs).

Shiny Mew would later be available in Emerald as a normal Shiny chance for the wild Mew encounter at Faraway Island (via the Japanese Old Sea Map distribution).

Gold

Silver

Shiny Mew would later be available in Emerald as a normal Shiny chance for the wild Mew encounter at Faraway Island (via the Japanese Old Sea Map distribution).

Unused Shiny Unown

To do:Find the sprites and post them here.

Every form of Unown also has Shiny variant, but due to how Unown's forms and Shininess were determined in Generation II, the only Unown forms that can be Shiny are its "I" and "V" ones.

Running Pokémon

Certain Pokémon in the games have a chance to flee from battle; this data is stored in three tables, in the order of increasing likelihood to flee. The first table is about a 10% chance with the second table being a 50% chance. However, the following Pokémon cannot be encountered in the wild, thus their running behavior remains unseen.

First table:

Eevee

Porygon

Togetic

Umbreon

Second table:

Articuno

Zapdos

Moltres

The third table, which guarantees escape, contains only the legendary beasts.

Slot Machine

An identifier (18) exists denoting a Bulbasaur symbol (using its doll sprite) in the Slot Machine interface. However, information such as how many coins the player will receive is undefined. The game can be forced to give a three-Bulbasaur payout by using the GameShark codes 011809C6, 01180DC6, and 011817C6.

Title Screen

The sprite data for Ho-Oh on the Gold title screen actually uses three colors, although the normal palette renders all three colors as black, meaning only its silhouette can normally be seen. The colored sprite can be seen through any glitch which causes the game to reset in mono Game Boy mode on a Game Boy Color (preventing the correct palettes from being loaded); the most reliable way of achieving this is listening to a Machop's cry in the Pokédex and then using the Coin Case.

The Lugia sprite in Silver is, however, stored using only the two colors visible in-game, suggesting either the decision to render them in silhouette was taken some time between the drawing of the two sprites, or that the original plan was to show Ho-oh in color but Lugia in silhouette, before a last-minute decision was made to make them both the same. This was restored in the remakes, including the Lugia model.

Unused Status Prevention Items

Located in the code of Gold, Silver, and Crystal are six unused hold items that would have prevented the Pokémon holding it from being inflicted with a status effect.

These items work perfectly except burned and frozen. While they still create the correct effect, the other four bring up the text "(Pokémon)'s protected by (item)!" These items aren't consumed after use, so they can be used indefinitely, much like the Leftovers. Burn and Freeze simply do the effect without telling the player anything.

It is unknown why these were left out, as it is likely these items would be the precursor to abilities introduced in Generation III that would prevent certain status effects, such as Immunity and Insomnia.

Identifier

Effect

14

Holder cannot be poisoned, similar to the Immunity ability.

15

Holder cannot be burned, similar to the Water Veil ability.

16

Holder cannot be frozen, similar to the Magma Armor ability.

17

Holder cannot fall asleep (Using Rest still works), similar to the Insomnia and Vital Spirit abilities.

18

Holder cannot be paralyzed, similar to the Limber ability.

19

Holder cannot be confused, similar to the Own Tempo ability.

Identifier

Effect

14

Holder cannot be poisoned, similar to the Immunity ability.

15

Holder cannot be burned, similar to the Water Veil ability.

16

Holder cannot be frozen.

17

Holder cannot fall asleep (Using Rest still works), similar to the Insomnia and Vital Spirit abilities.

18

Holder cannot be paralyzed.

19

Holder cannot be confused, similar to the Own Tempo ability.

Unused Venomoth possibility in Bug-Catching Contest

The games use a list of possibilities, Pokémon species and a level range to generate Pokémon caught by the other contestants in the Bug-Catching Contest. The list contains an unused entry for a Venomoth between level 30 and 40, probably because Venomoth is not a Pokémon that can be caught in National Park. The table is identical in Gold, Silver and Crystal.

Version Differences

Changed Graphics

Name Entry Screen

Every one of these versions have a peculiar difference compared to the other versions:

The Japanese version writes the name one tile higher and one tile more to the right.

The international versions allow up to seven characters to be entered.

The Korean version does not have an option to change the character set unlike the Japanese and international versions.

Summary Screens

Japanese

International

Korean

In the Japanese and Korean versions of the game, Pokémon summary screens are vertically aligned, similar to Ruby and Sapphire onwards in localized games. In the international releases, due to the lack of space, they were reverted to the horizontally aligned screens of Red, Green, Blue and Yellow.

Trading Screen

In the Japanese and Korean versions of the game, the Pokémon trading screen is vertically aligned. In the international releases, due to the lack of space, it is horizontally aligned.

PC Boxes

Japanese

International

Korean

The amount of PC boxes in the Pokémon Storage System was changed from to 9 to 14 in the localizations (including the Korean ones) due to the maximum number of Pokémon per box being decreased from 30 to 20.

The Japanese text-box frames here are also positioned one pixel higher than the ones in the other versions.

Pokémon Storage System Layout

Japanese

International

Korean

In the Japanese and Korean versions, the Pokémon in the Pokémon Storage System's layout is enclosed in a text-box frame and the Pokémon list appears in the background. In the other localizations, there is no frame surrounding the Pokémon but the Pokémon list appears in a text-box frame.

Also, the Japanese text-box frames positions are one pixel higher and the Pokémon level number is one pixel lower than the ones in the Korean version.

Poké Mart And Pokémon Center Signs

Japanese / Korean

English

French / Spanish

German / Italian

In the Japanese and Korean versions, the sign of Pokémon Centers in Johto have a Poké Ball drawing with the letters PC next to it. In the localizations, the sign was changed back to the one used in Red, Green, Blue and Yellow. The Pokémon Center signs in Kanto use the old design in all versions.

Nidoran Gender Symbol

Japan/Korea

International

In the localizations, the gender symbol for the Nidoran is shown twice during battles due to the gender symbol being placed next to the level indicator instead of next to the Pokémon's name as in the Japanese and Korean versions.

SonicBoom

Japan/Korea

International

In the Japanese and Korean versions, SonicBoom's animation is a shock wave hitting the opponent. For undisclosed reasons, it was changed to a tornado hitting the opponent in the localizations, making it very similar to Gust.

Coin Case Bug

Due to an error in the North American localizations, the text box printed when using the Coin Case is improperly terminated in the English version, as a 57 character is used instead of a 50 (the original value in the Japanese versions of Gold/Silver), causing the game to jump to a section of memory used for storing sound effects. This section of memory is usually empty, unless you listened to a Pokémon's cry right before in which case the game interprets the Pokémon's cry as code, leading to arbitrary code execution.

This bug isn't present in the original Japanese release, the non-English European translations, or the Korean ones.

Korean Version

The error message stating that the game is only playable on Game Boy Color.

To do:Are the printer options merely hidden?

이 카트리지는 게임보이 컬러 전용입니다. 게임보이 컬러에서 사용을 부탁드리겠습니다.
(This cartridge is only for Game Boy Color. Please run it with Game Boy Color.)

The Korean versions of Gold and Silver, like Crystal, are only compatible with the Game Boy Color. Previous versions of Gold and Silver can be run on Game Boy mode. This is due to the fact that the Korean version uses the Game Boy Color's second bank of VRAM for printing its text, rendering it incompatible with the regular Game Boy, which is the reason why it displays random tiles for text when force-booted into Game Boy mode.

When the player attempts to run the game on an original Game Boy, they receive a message stating that the game is only compatible on the Game Boy Color. The message is very plain compared to Crystal, and without borders. However, it is still possible to force-boot the game into Game Boy mode through editing address 0xFFE8 to 0x01 or by entering the GameShark code 0101E8FF. The game will still run, but there will be a glitchfest of random tiles for text, sprites refusing to display, random slowdowns, and other strange behavior. Most of the time, the game will also randomly crash when it's booted up in this state, although it usually doesn't happen immediately after boot-up.

To do:Shouldn't we investigate the crashes a little further?

Both Gold and Silver left their respective Super Game Boy border unused. They are the English design, rather than Japanese.

Additionally, Game Boy Printer support has been removed as the accessory was not released in South Korea.

Also, this version of the game has its own version of the English credits at the end of the game, replacing the English translation staff with the Korean translation staff.

International Linking

To do:Which Hangul characters can be misinterpreted as control codes?

Western language Pokémon games(languages doesn't matter) can be connected to each other. However, alphabet letters with diacritics such as ecutes and umlauts(except é, this exists in even English Pokémon games to print Pokémon) may cause mojibake(character transform) in other language games which doesn't support.

Japanese Pokémon games can only be connected to Japanese Gen I and II Pokémon games. Otherwise, two games connected to each other will be crashed because the positions of data structures and codes in Japanese games are different to non-Japanese Pokémon games.

Korean Pokémon games, however, can be connected to other Western Pokémon games(of course Korean, too.) including Generation I and Crystal without serious problems. It's the reason that Korean Pokémon games are based on English ones though their graphics are similar to Japanese ones. English alphabets and character encodings are programmed in Korean Pokémon games(the Korean games use it in the credits and a few other places). By using this, Gen I exclusive Pokémon(Bulbasaur, Charmander, Squirtle, etc.) can be obtained in Korean Pokémon games. Thus, completing Pokédex(except Mew and Celebi without glitch) can be possible in these games, too.

However using this feature leads to issues for both sides: In the Korean games, names longer than 5 characters appear shortened or overflow in places. Also, characters with diacritics may cause mojibake in Korean games. And in the non-Korean games, Korean names become gibberish (non-Korean games were incapable of displaying them until Black and White) or cause the link to fail (certain Hangul are misinterpreted as control codes).

Stadium 2 Compatibility

The Korean games are recognised as valid Pokémon games by the Western versions of Stadium 2, but the game is unable to load the save data for it. On the other hand, the Japanese version of Stadium 2 doesn't even recognise the Korean GS games as valid Pokémon games.
Transferring Korean Pokémon into Western GSC games allows them to be used in Stadium 2 without issues (except for the name corruption).

Exclusive Pokémon

In Japan and South Korea, Phanpy and Donphan are found in the wild in Gold while Teddiursa and Ursaring are found in the wild in Silver. In the rest of the world, these were switched.

Interestingly, this localization change was not made for the international versions of HeartGold and SoulSilver – Phanpy and Donphan are found in HeartGold while Teddiursa and Ursaring are found in SoulSilver, regardless of region.

Kings

The team of Pokéfan Alex, a Trainer found on Route 13, is made of Pokémon that have names ending in "king" (キング). Due to Magikarp not sharing this trait in the English versions (its Japanese name is コイキング/Koiking), it was replaced by Seaking in order to stay true to the theme. Unlike Magikarp, which is level 58, the Seaking is level 29 like the rest of his team. In the Korean versions, his team is the same as in the Japanese versions since Magikarp's Korean name is 잉어킹 (Ingeoking) and both Nidoking and Slowking also have the word "king" (킹) in their Korean names.

Like the aforementioned change to the exclusive Pokémon, this was not replicated in HeartGold and SoulSilver since Alex still has a Magikarp in the localizations, which is now level 65.

National Park glitch

The Japanese versions of Gold and Silver have a glitch that is very similar to the Safari Zone glitch in Pokémon Red and Blue, but instead of warping to Glitch City, it allows you to create glitch Pokémon.

Fill your party with Pokémon. Make sure your first Pokémon knows Fly or Teleport.

Once in, immediately step out. When the guard asks you if you want to quit, say no.

Once back in, Fly or Teleport out of the National Park.

Go to a Pokémon Center and deposit the second Pokémon in the PC.

Save the game and reset the console.

Head back to the Bug-Catching Contest and quit the contest.

After the results are announced, you will have a new Pokémon in your party with the species of the second Pokémon you had in your party at step 1, but with all other information (including stats, moves, gender, DVs, and shininess) copied from the sixth Pokémon. The stats will reset once the Pokémon evolves, but the species will reset to what it should be if this Pokémon is given to the daycare.

This glitch was fixed in the localized versions of Gold and Silver, and does not occur in any version of Crystal.